Table of Contents
Access denied ErrorsThis chapter covers topics that deal with administering a MySQL installation:
Configuring the server
Managing user accounts
Performing backups
The server log files
The query cache
The MySQL server, mysqld, is the main program that does most of the work in a MySQL installation. The server is accompanied by several related scripts that perform setup operations when you install MySQL or that assist you in starting and stopping the server. This section provides an overview of the server and related programs. The following sections provide more detailed information about each of these programs.
Each MySQL program takes many different options. Most programs
provide a --help option that you can use to get a
description of the program's different options. For example, try
mysqld --help.
You can override default option values for MySQL programs by specifying options on the command line or in an option file. Section 4.3, “Specifying Program Options”.
The following list briefly describes the MySQL server and server-related programs:
The SQL daemon (that is, the MySQL server). To use client programs, mysqld must be running, because clients gain access to databases by connecting to the server. See Section 5.2, “mysqld — The MySQL Server”.
A server startup script. mysqld_safe attempts to start mysqld. See Section 5.3.1, “mysqld_safe — MySQL Server Startup Script”.
A server startup script. This script is used on systems that use System V-style run directories containing scripts that start system services for particular run levels. It invokes mysqld_safe to start the MySQL server. See Section 5.3.2, “mysql.server — MySQL Server Startup Script”.
A server startup script that can start or stop multiple
servers installed on the system. See
Section 5.3.3, “mysqld_multi — Manage Multiple MySQL Servers”. An alternative to
mysqld_multi is
mysqlmanager, the MySQL Instance Manager.
See Section 5.4, “mysqlmanager — The MySQL Instance Manager”.
The MySQL Instance Manager, a program for monitoring and managing MySQL servers. See Section 5.4, “mysqlmanager — The MySQL Instance Manager”.
There are several other programs that are related to MySQL installation or upgrading:
This program is used during the MySQL build/installation process. It compiles error message files from the error source files. See Section 5.5.1, “comp_err — Compile MySQL Error Message File”.
This program makes a binary release of a compiled MySQL. This
could be sent by FTP to
/pub/mysql/upload/ on
ftp.mysql.com for the convenience of other
MySQL users.
This program is used on Windows. It packages a MySQL distribution for installation after the source distribution has been built. See Section 5.5.2, “make_win_bin_dist — Package MySQL Distribution as ZIP Archive”.
This program is used after a MySQL upgrade operation. It updates the grant tables with any changes that have been made in newer versions of MySQL. See Section 5.5.3, “mysql_fix_privilege_tables — Upgrade MySQL System Tables”.
Note: As of MySQL 5.1.7, this program has been superseded by mysql_upgrade.
This script creates the MySQL database and initializes the grant tables with default privileges. It is usually executed only once, when first installing MySQL on a system. See Section 2.10.2, “Unix Post-Installation Procedures”, and Section 5.5.4, “mysql_install_db — MySQL Data Directory Initialization Script”.
This program enables you to improve the security of your MySQL installation. SQL. See Section 5.5.5, “mysql_secure_installation — Improve MySQL Installation Security”.
This program loads the time zone tables in the
mysql database using the contents of the
host system zoneinfo database (the set
of files describing time zones). SQL. See
Section 5.5.6, “mysql_tzinfo_to_sql — Load the Time Zone Tables”.
This program is used after a MySQL upgrade operation. It checks tables for incompatibilities and repairs them if necessary, and updates the grant tables with any changes that have been made in newer versions of MySQL. See Section 5.5.7, “mysql_upgrade — Check Tables for MySQL Upgrade”.
mysqld is the MySQL server. The following discussion covers these MySQL server configuration topics:
Startup options that the server supports
Server system variables
Server status variables
How to set the server SQL mode
The server shutdown process
Note: Not all storage engines
are supported by all MySQL server binaries and configurations.
To find out how to determine which storage engines are
supported by your MySQL server installation, see
Section 13.5.4.13, “SHOW ENGINES Syntax”.
The following table provides a list of all the command line
options, server and status variables applicable within
mysqld.
The table lists command line options (Cmd-line), options valid in configuration files (Option file), server system variables (Server Var), and status variables (Status var) in one unified list, with notification of where each option/variable is valid. If a server option set on the command line or in an option file differs from the name of the corresponding server system or status variable, the variable name is noted immediately below the corresponding option. For status variables, the scope of the variable is shown (Scope) as either global, session, or both. Please see the corresponding sections for details on setting and using the options and variables. Where appropriate, a direct link to further information on the item as available.
This table is part of an ongoing process to expand and simplify the information provided on these elements. Further improvements to the table, and corresponding descriptions will be applied over the coming months.